Underneath Orte's old town runs an extensive system of tunnels, cisterns, and cellars cut into the soft tufa rock. Some chambers are Etruscan, others Roman, others medieval, and many were modified continuously down the centuries — used in turn for storing water, ageing wine, sheltering from raids, and dumping rubbish. Guided tours are run by the local cultural association and depart from the tourist office, usually on weekends.
The visit lasts about an hour and a half and covers two or three connected sections, including the enormous Roman cistern beneath Piazza della Libertà. Bring a jacket: the temperature inside stays around 14°C year-round.